4. Where a lot of them go wrong, I think, is in just saying "homosexuality is wrong" without being specific in what they mean. I think it's pretty clear that as humans we don't always choose what to crave or desire, and that very few people choose to crave romantic/sexual intimacy with their same sex; one way or another that desire just kind of happens to some people. What matters is what desires we act upon, and when. In other words, just BEING gay is not a sin, per se, it's choosing to feed and act on that that's wrong. And honestly, I think someone who pursues their same sex romantically when they don't know about the Lord, or in their heart of hearts don't know of any good reason to believe what they're doing is wrong, is not culpable in God's eyes. Some people say that it's cruel and unusual to ask gay people to just constantly stuff their desires away, never to act on them. I don't really blame them for saying so, but honestly, for a religion of people working towards becoming a totally new person or being completely "born again", I don't think putting away your homosexual tendencies is a ludicrous thing to ask. Could I consistently put such desires aside if I were gay? I honestly don't know, but that's where forgiveness comes in. The Lord forgives sins again and again, and we should all try to do so as well.
5. As for transgenderism, I think most Christian sects interpret the beginning of Genesis as implying that our God-given sex is sacred, therefore we shouldn't seek to abandon it in favor of something else. Again, that doesn't mean that there aren't people who deeply dislike being the sex that they are, or that such people have sinned by simply having those dysphoric feelings.